It looks like some kind of mold or special measuring device. Is that a hole in the side……perhaps a special venting hole for when the poured mixture reaches certain level or designed to separate two liquids. Not 20 questions here, but is that a hole in the side (I think it is time for a hint)?

i've been looking at this for days and can't even come up with a reasonable guess. i'd like to see another view of it - is it hollow inside or is it solid? hard to tell how big it is, up until now i'm assuming that it's about 4 to 6 inches in diameter? boy does this have me stumped.